bars on graphs

[Paolo Ariano]

Hi all,

after analyzing my data (cell's fluorescence) i obtain two files one
with changes of fluorescence values in time (file1.txt) and another with
changes in conditions during the experiment (file2.txt)

file1.txt
Time    cell1   cell2
0       0.92    0.27
10      0.95    0.35
20      0.93    0.24
30      0.90    0.29

file2.txt
Time
10      solution A
50      solution B

i plot file1.txt but i'd like to superimpose bars of different colors
with changes in solutions from file2.txt, does somebody have an idea on
how to put bars on the graps ?

thanks
paolo
-- 
Neuroscience PhD
Post-doc @ University of Torino
www.personalweb.unito.it/paolo.ariano
www.cellular-neurophysiology.unito.it
www.mieleria.it